Not applicable.
Not applicable.
The present invention relates to splitter and cutting member guard assemblies for table saws and other cutting devices including a rotating, oscillating, or otherwise driven cutting member that is at least partially surrounded by a workpiece support surface. More particularly, the present invention relates to splitter and cutting member guard assemblies wherein the cutting member guard hood may be disposed in at least two positions relative to the splitter of the assembly, and wherein the positions include a first position, in which the cutting member guard hood covers a portion of the cutting device""s cutting member, and a second position, in which that portion of the cutting member is not covered by the cutting member guard hood and is accessible to an operator. The present invention finds application in any field in which it is desirable to prevent operator contact with a rotating, oscillating, or otherwise driven cutting member, but wherein certain operations, such as installation or replacement of the cutting member, require that the cutting member and its mounting point are accessible to an operator. Examples of possible fields of application of the present invention include the woodworking field as used with, for example, table saws, as well as in any field in which cutting devices of a generally similar construction are used to separate or otherwise remove a portion of a workpiece.
In several fields, devices for cutting workpieces are known that include a substantially planar, generally horizontally disposed, workpiece support surface through which a portion of a rotating or oscillating cutting member is exposed. A familiar example is an electric table saw, which typically includes a table portion having a support surface for supporting a workpiece, a frame for supporting or bracing the table portion at an appropriate elevation, and a circular saw blade that is disposed through a void in the table portion so that an operative portion of the saw blade is disposed above the workpiece support surface and may contact and cut a workpiece advanced along the support surface. The xe2x80x9coperative portionxe2x80x9d of the saw blade is that portion of the saw blade that is disposed above the support surface and may contact and cut a workpiece advanced along the support surface. Table saws have included a saw blade guard hood for covering the operative portion of the saw blade to prevent operator contact with the saw blade and limit the ejection of cutting debris. Table saws have also included a splitter for entering into the workpiece kerf so as to reduce the possibility of workpiece binding as the workpiece is severed by the saw blade. The saw blade guard hood may be movably connected to the splitter to provide a splitter and saw blade guard assembly. The splitter portion of the assembly is fixedly connected to some portion of the table saw such as the table portion and/or frame, and is mounted in line with the saw blade. As the workpiece contacts the forward face of the saw blade guard hood the hood moves relative to the splitter and is forced upward allowing the workpiece to advance into the rotating saw blade. As the workpiece advances along the workpiece support surface past the saw blade, the splitter enters the kerf cut in the workpiece.
The circular saw blade of a table saw typically is mounted on a rotating spindle or arbor located beneath the table portion, and the spindle may be raised or lowered to appropriately adjust the elevation of the portion of the saw blade positioned above the workpiece support surface. In order to facilitate access to the arbor through the table portion so that the saw blade may be installed or replaced, the saw blade typically extends through a void in the table portion that is substantially wider and longer than the saw blade""s cross-section. A table insert is disposed in the void when the table saw is in operation, and the table insert includes an appropriately sized slot through which the saw blade passes. To access the arbor through the table portion, the saw blade guard hood is removed or moved to allow access to the portion of the saw blade disposed above the workpiece support surface, and the table insert is then removed from the void in the table portion.
The ease by which an operator may access the arbor through the table portion is influenced by the particular construction of the splitter and saw blade guard assembly. In one known construction, shown in FIG. 6, a splitter and saw blade guard assembly 110 is fixedly connected to a table saw 111, shown in cross-section, along a line coincident with a longitudinal axis of the slot in the table insert, including a table portion 112 having a generally planar workpiece support surface 113, a frame 114 for supporting the table portion 112, and a rotating circular saw blade 116. The assembly 110 includes a splitter 118 having two posts 120 and 122 for fixedly connecting the splitter 118 to the table portion 112 and the frame 114, respectively. The splitter 118 is aligned with the saw blade 116 so that the splitter 118 enters the kerf of a workpiece (not shown) that has been cut by the saw blade 116 (advanced rightwardly in FIG. 6). The saw blade 116 passes through a table insert slot, the position of which is indicated generally as 126, and the table insert 117 is disposed in a void in the table portion 112. The assembly 110 also includes a saw blade guard hood 128 that is movably connected to the splitter 118 by a pivot member 130 that is, in turn, rotatably connected to the hood 128 at a first rotation point 132 and that is rotatably connected to the splitter 118 at a second rotation point 134. Suitable rotation of the pivot member 130 about on one or both rotation points 132 and 134 allows the hood 128 to assume a first position, wherein it covers the portion of the saw blade 116 disposed above the support surface 113, and a second position, wherein that portion of the saw blade 116 is not covered by the hood 128, and intermediate positions. FIG. 6 shows the second position, and the general direction of movement of the hood 128 from the first position to the second position is indicated by the curved arrow. The pivot member 130 is constructed so that it may not rotate about the second rotation axis 134 in the clockwise direction as depicted in FIG. 6 beyond the position shown in FIG. 6. Thus, the mass of the hood 128 causes the hood 128 to fall downward in the direction opposite to the curved arrow from the second position shown in FIG. 6 to the first position, and such movement would interfere with an operator""s removal of the table insert 117 to, for example, access the arbor through the void table portion 112 to mount or replace the saw blade.
FIG. 7 depicts another existing splitter and saw blade guard assembly, generally designated as 210, for use with a table saw 211 and generally including a saw blade guard hood 212 movably connected to a splitter 214 by pivot member 216. As in FIG. 6, FIG. 7 shows the table saw 211 in cross-section along a longitudinal line through the slot in the saw""s table insert 224. As in the assembly 110 depicted in FIG. 6, the pivot member 216 is rotatably connected to the hood 212 at a first rotation point 218 and to splitter 214 at a second rotation point 220. By rotating pivot member 216 about second rotation point 220 in the clockwise direction indicated by the arrow in FIG. 7, the hood 212 may be moved from a first position, in which the hood 212 is disposed over both the portion of the saw blade 222 disposed above the workpiece support surface 213 and the table insert 224 through which the saw blade 222 is disposed, and a second position, shown in FIG. 7, in which the operative portion of the saw blade 222 is uncovered and the table insert 224 may be removed from the void 228 in the saw""s table portion 226 without interference from the hood 212. The assembly 210 is designed so that the pivot member 216 may rotate beyond the point that may be attained in the assembly 110 of FIG. 6, thereby allowing the hood 212 to be retained in the depicted second position by the force of gravity. Although the assembly 210 provides some advantage over assembly 110 of FIG. 6 in that the hood 212 of assembly 210 will remain in the second position and allow unhindered removal and re-installation of the table insert 224, an operator must manually rotate the hood 212 back to the first position from the second position after the table insert 224 has been re-installed in the void 228 and before operating the table saw 211.
Considering the limitations inherent in the known table saw splitter and saw blade guard assemblies, the need exists for an improved assembly. More generally, a need exists for an improved splitter and cutting member guard assembly for table saws and other cutting devices that include a rotating or oscillating cutting member having an operative portion that is at least partially surrounded by a workpiece support surface.
The present invention addresses the forgoing needs, among others, by providing an improved splitter and cutting member guard assembly. The assembly of the present invention is intended for mounting on a table saw or other similarly constructed device that includes a circular saw blade or other rotating or oscillating cutting member and that includes a workpiece support surface at least partially surrounding an operative portion of the cutting member. The assembly of the present invention includes (i) a cutting member guard hood for covering an operative portion of the cutting member and (ii) a splitter for passing through a workpiece kerf as the workpiece is fed past the splitter. The cutting member guard hood (which, when the assembly is constructed for use with a table saw, may be in the form of a saw blade guard hood) is movably mounted to the splitter and is pivotable or otherwise movable relative to the splitter between a first position, in which the cutting member hood covers the operative portion of the cutting member, and a second position, in which the operative portion of the cutting member is exposed. As such, the first and second positions may correspond to a raised position and lowered position, respectively, of the cutting member guard hood.
The assembly of the present invention is constructed so that the cutting member guard hood may be retained in the second position, which facilitates operator access to the saw blade, table insert, and, on removal of the table insert, arbor. To provide for retention of the hood in the second position, the assembly of the present invention may include first and second retention elements as follows: the cutting member guard hood may include a first retention element and the splitter may include a second retention element, and the retention elements may selectively co-act so as to connect the cutting member guard hood and the splitter, either directly or indirectly, to thereby retain the cutting member guard hood in the second position.
As used herein, the term xe2x80x9cco-actxe2x80x9d refers to the concerted action of the first and second retention elements, either by their engagement, coupling, linkage, etc., together, either directly or indirectly, so as to connect the cutting member guard hood to the splitter.
The splitter and cutting member guard assembly of the present invention may be constructed for attachment to a cutting device such as, for example, a table saw, wherein the cutting device includes a table portion, a void defined in the table portion, and a table insert disposed within the void, and wherein the table insert includes a slot therethrough through which the circular saw blade or other cutting member of the device may extend and that is removable from the table portion to provide an operator access through the table portion. In the assembly of the present invention, the table insert must be removed from the void in the table portion to allow the first retention element to co-act with the second retention element to thereby retain the cutting member guard hood in the second position.
The cutting member guard hood may be movably mounted to the splitter by, for example, a pivot assembly that is movably mounted to both the cutting member guard hood and the splitter and that allows the cutting member guard hood to assume both the first and second positions, as well as positions intermediate the first and second positions. In one configuration, the pivot assembly may include a pivot member having first and second ends. The first end is rotatably connected to the cutting member guard hood about a first axis of rotation and the second end is rotatably connected to the splitter about a second axis of rotation. The cutting member guard hood is movable between the first and second positions by rotating the pivot member about at least the second rotation axis relative to the splitter.
The splitter and cutting member guard assembly of the invention also may be constructed so that the cutting member guard hood is biased toward the first position. In one construction of the invention, the individual elements of the invention are configured and arranged so that the force of gravity acting upon the masses of the movable elements of the invention will urge the cutting member guard hood toward its first position.
The first retention element of the cutting member guard hood may be, for example, a projecting portion of the hood, such as a tab or other projection, and the second retention element of the splitter may be, for example, a first recess defined by the perimeter of the splitter. In that arrangement, the projecting portion of the hood may be disposed within the splitter""s first recess when the cutting member guard hood is in the second position, and the engagement of the projecting portion and first recess will retain the hood in the second position unless disturbed. The splitter also may include a second recess, which also may be formed by the perimeter of the splitter, to receive the projecting portion of the cutting member guard hood when the hood is in the first position.
As indicated above, according to one aspect of the splitter and cutting member guard assembly of the present invention, the cutting member guard hood may not be placed into the second position, and cannot be retained in that position, unless the table insert has been removed from the void in the table portion of the cutting device. That aspect of the invention may be accomplished by, for example, defining a table insert plane which includes a surface of the table insert when the table insert is disposed within the void in the table portion of the cutting device. The cutting member guard hood is constructed and arranged so as to intersect the table insert plane and a region of the hood is disposed within the void in the table portion when the hood is in the second position, while the hood neither intersects the table insert plane nor is partially disposed within the void in the table portion when the hood is in the first position. Thus, the table insert of the cutting device must be removed from the void in order to, for example, allow engagement or other co-action of the first and second retention elements to retain the cutting member guard hood in the second position.
According to yet another aspect of the present invention, the invention is directed to a splitter and cutting member guard assembly for mounting on a cutting device having a rotating or reciprocating cutting member, a table portion having a workpiece support surface, a void defined in the table portion, and a removable table insert that is selectively positionable within the void and that includes a slot to allow at least a portion of the cutting member to protrude therethrough. The assembly includes a splitter for passing through a workpiece kerf and a cutting member guard hood for selectively covering an operative portion of the cutting member. (The cutting device may be, for example, a table saw, in which case the cutting member may be a circular saw blade and the cutting member guard hood may be a saw blade guard hood.) The cutting member guard hood is movably connected to the splitter and is positionable between a first position, in which the cutting member guard hood covers a portion of the cutting member exposed above the workpiece support surface, and a second position, in which the portion of the cutting member is not covered by the cutting member guard hood. A portion of the cutting member guard hood is selectively engageable, either directly or through intermediate elements, with a portion of the splitter to retain the hood in the said second position, and the hood is prevented from engaging the splitter to retain the hood in the second position if the table insert is positioned within the void in the table portion. For example, the assembly may be constructed so that a region of the cutting member guard hood is disposed in the void in the table portion when the cutting member guard hood is in the second position.
As indicated above, the splitter and cutting member guard assembly of the present invention may be adapted for use with a table saw including a circular saw blade. In such configuration, the assembly of the invention may be in the form of, for example, a splitter and saw blade guard assembly including (i) a circular saw blade guard hood for covering the operative portion of the circular saw blade which protrudes through the slot in the table insert of the table saw and (ii) a splitter for entering the workpiece kerf after the cut workpiece passes beyond the circular saw blade. The saw blade guard hood is movably connected to the splitter and is movable relative to the splitter between at least a first position, in which the saw blade guard hood covers the operative, protruding portion of the circular saw blade, and a second position, in which the operative portion of the circular saw blade is not covered by the saw blade guard hood. The saw blade guard hood is selectively engageable or otherwise connectable to the splitter, either directly or indirectly through intermediate elements, to thereby retain the saw blade guard hood in the second position. However, the saw blade guard hood may only be retained in the second position by the foregoing engagement of elements if the table saw insert has been removed from the void in the table saw""s table portion, and this feature may be achieved by, for example, configuring the elements of the assembly so that the saw blade guard hood intersects the table insert plane when the hood is in the second position. Thus, the saw blade guard is thereby prevented from being retained in the second position when the table insert is positioned within the void in the table portion.
The present invention also is directed to a cutting device including a splitter and cutting member guard assembly constructed according to the present invention, and the cutting device also may include a rotating or reciprocating cutting member, a table portion having a workpiece supporting surface and also having a void therethrough for passage of a portion of the cutting member, a frame for supporting the table portion, and a table insert that is selectively positonable within the void and that includes a slot for passage of the cutting member therethrough. According to an aspect of the invention, the cutting device of the present invention may be, for example, a table saw having a cutting member in the form of a rotating circular saw blade and further including a splitter and cutting member guard assembly constructed according to the present invention and in the form of splitter and saw blade guard assembly.
According to a further aspect of the present invention, a cutting device in the form of a table saw constructed according to the present invention includes:
a table portion having a void therethrough and including a support surface for supporting a workpiece;
a frame on which the table portion is mounted;
a table insert that is selectively positionable within the void and that includes a slot through which the table saw""s circular saw blade may extend; and
a splitter and saw blade guard assembly which may be, for example, directly or indirectly mounted to at least the frame and/or the table portion, including a saw blade guard hood, for covering an operative portion of the circular saw blade exposed above the table insert, and a splitter, and wherein the saw blade guard hood is movably mounted to the splitter and is movable relative to the splitter between a first position, in which the saw blade guard hood covers the operative portion of the circular saw blade protruding through the table insert, and a second position, in which the operative portion of the circular saw blade is not covered by the hood, and wherein the saw blade guard hood includes a first retention element that selectively may co-act, either directly or indirectly through intermediate elements, with a second retention element defined by the splitter, to thereby retain the saw blade guard hood in the second position, and further wherein the first retention element is incapable of co-acting with the second retention element to retain the saw blade guard in the second position when the table insert is positioned within the void in the table portion.
According to an additional aspect of the present invention, the invention provides for a cutting device in the form of a table saw including a rotating circular saw blade and further including:
a table portion having a void therethrough and including a support surface for supporting a workpiece;
a frame on which the table portion is mounted;
a table insert that is selectively positionable within the void and that includes a slot through which the circular saw blade may extend; and
a splitter and saw blade guard assembly, which may be, for example, mounted, either directly or indirectly through one or more intermediate elements, to at least the frame and/or the table portion, including a splitter for passing through a kerf cut in a workpiece by the circular saw blade and including a first retention structure thereon, and a saw blade guard hood, including a second retention structure thereon, for preventing an operator from contacting a portion of the circular saw blade, and wherein the saw blade guard hood is pivotally mounted to the splitter and is positionable in at least a first position, in which the saw blade guard hood covers a portion of the circular saw blade, and a second position, in which the portion of the circular saw blade is not covered by the saw blade guard hood, and further wherein one of the two retention structures may engage the other of the two retention structures to provide a retained configuration in which the saw blade guard hood is retained in the second position, and also wherein the retention structures are incapable of assuming the retained configuration when the table insert is positioned within the void in the table portion.
The splitter and cutting member guard assembly of the present invention provides an improvement over the existing assemblies. In particular, and as further described below, the splitter and cutting guard assembly of the present invention provides for retention of the cutting member guard hood in a position allowing operator access to the cutting member and the table insert so that the insert may be removed and the cutting member, both above and below the table insert, is conveniently accessible to an operator. The invention may be configured as necessary to adapt it to the particular application in which it is used and is useful in such adaptations as, for example, a splitter and saw blade guard member assembly for a table saw having a rotating circular saw blade or other rotating cutting member.
The reader will appreciate the foregoing details and advantages of the present invention, as well as others, upon consideration of the following detailed description of embodiments of the invention. The reader also may comprehend such additional details and advantages of the present invention upon using the invention.